Erosion and Sediment Delivery in Iowa

Posted on February 8th, 2018

The Iowa Geological Survey has been working on updating the USDA’s aging report on erosion and sediment delivery in Iowa which used data gathered in the 1970’s to estimate how much soil actually reaches Iowa streams.

Sediment delivery is important to understand since even current estimates of soil erosion do not specify where eroded soil is re-deposited.

Our initial study in a sub basin of the Rapid Creek watershed in Johnson County, Iowa has shown that current rates of sediment delivery are approximately 3 times lower than rates from the 1970’s (4% down from 12%).

This is extremely encouraging and shows the positive impacts of 4 decades of agricultural conservation practices in Iowa.